Add a regression test for #147971

Author: cuviper

library/std/tests/ambiguous-hash_map.rs

@@ -0,0 +1,17 @@
+/// Make sure that a `std` macro `hash_map!` does not cause ambiguity
+/// with a local glob import with the same name.
+///
+/// See regression https://github.com/rust-lang/rust/issues/147971
+
+mod module {
+    macro_rules! hash_map {
+        () => {}
+    }
+    pub(crate) use hash_map;
+}
+
+use module::*;
+
+fn main() {
+    hash_map! {}
+}